A process for producing molded tableware by mixing plant fiber pulp and modified starch

Abstract

The present application relates to wet pressing moulding technical field, specifically to a kind of plant fiber paper pulp moulding and modified starch mixed moulding tableware production process, including the present application relates to a kind of plant fiber paper pulp moulding and modified starch mixed moulding tableware production process.The process first year of age Gramineae plant fiber pulp board is carried out pulping treatment, so that it has reasonable fiber knapping degree, then mixed configuration and dispense pulp concentration, during applying fluoride-free oil-proof agent to improve pulp quality.After uniform stirring continuously, prevent pulp fiber deposition, pulp is injected into forming mould, plant fiber is evenly distributed by vacuum effect, while excess moisture is backflowed, reaches about 70% moisture content.The process improves the stiffness of product by spraying process technology, which can be increased by 57% at most.The application of modified starch spraying surface process also avoids the problems of sizing filterability, blocking and sticking in pulp.The application of modified starch greatly improves the production efficiency of product.

Description

Technical Field

[0001] This invention relates to the field of wet pressing molding technology, and in particular to a production process for tableware made by molding plant fiber pulp and modified starch mixture. Background Technology

[0002] Traditional tableware production typically employs pulp molding technology, using wood fiber pulp as its main raw material. The pulp is molded under high temperature and pressure before further processing. However, this traditional process has several drawbacks:

[0003] Firstly, traditional processes often use fluorinated oil-repellent agents to improve the water and oil resistance of tableware. However, these fluorinated oil-repellent agents release harmful fluorides, posing a potential threat to the environment and health, and do not meet modern environmental protection requirements.

[0004] Secondly, traditional processes often use internal sizing to improve the water filtration performance of products, but this can easily lead to filter clogging and affect production efficiency.

[0005] In addition, starch curing in traditional processes usually requires a separate hot pressing process, which consumes additional energy and time.

[0006] To address these issues, this invention proposes a novel tableware manufacturing process. By using modified starch to replace traditional fluorinated oil-resistant agents, it not only solves environmental problems but also reduces production costs. Simultaneously, the online spraying and hot-pressing method enables rapid starch curing, saving energy consumption. Furthermore, the spraying technology improves product stiffness and increases production efficiency. In summary, this innovative process enhances product quality while offering significant environmental and economic benefits, demonstrating broad application prospects. Summary of the Invention

[0007] In view of this, the purpose of this invention is to propose a production process for tableware made by molding plant fiber pulp and modified starch mixture, so as to solve the above-mentioned problems.

[0008] To achieve the above objectives, the present invention provides a production process for tableware made by molding plant fiber pulp and modified starch mixture.

[0009] A process for producing tableware using a mixture of plant fiber pulp molding and modified starch molding includes the following steps:

[0010] Step 1: Pulp the one-year-old grass fiber board through a low-concentration hydraulic pulper for about 2.5 minutes to achieve a reasonable fiber disintegration degree, and then transport the pulp to the mixing tank.

[0011] Step 2: In the mixing tank, the concentrated slurry is mixed and prepared in a certain proportion and stirred evenly to adjust the concentration of the slurry to 0.4%. During the pulping process, a fluorine-free anti-oil agent is applied to the slurry.

[0012] Step 3: The prepared low-concentration slurry is pumped to the slurry supply tank and continuously stirred evenly to prevent slurry fiber sedimentation.

[0013] Step 4: Inject the prepared slurry into the metal mesh of the molding mold through a slurry pump. Apply vacuum for about 10 seconds to evenly distribute the plant fibers on the metal mesh. At the same time, remove an appropriate amount of water, about 70%, and return the excess water to the water supply tank.

[0014] Step 5: Transfer the formed wet blank to the hot pressing and shaping moving mold using a robotic arm.

[0015] Step 6: Add the modified corn starch to the spray can, mix it with water at a ratio of 0.2%, and stir continuously.

[0016] Step 7: Use a spray gun to move the nozzle and spray the mixed starch solution evenly onto the wet blank in the hot press mold for about 5 seconds.

[0017] Step 8: After the spraying is completed, the hot press bottom mold moves to the bottom of the hot press upper mold. The upper mold starts to perform hot pressing for about 30-40 seconds. The equipment pressurizes to 120 tons until the moisture content after hot pressing does not exceed 7%.

[0018] Step 9: When the upper mold returns to its original position, use a robotic arm to move the hot-pressed tableware to the edge-cutting mold for die-cutting, and recycle the excess edge material.

[0019] Step 10: After trimming, the products are selected, disinfected, packaged, and put into storage.

[0020] Furthermore, the raw materials for plant fiber pulp boards include any one of sugarcane, reeds, bamboo, rice straw, and wheat, which are annual grasses.

[0021] Furthermore, the plant-modified starch is modified corn starch.

[0022] Furthermore, when spraying the starch solution, the spraying time is approximately 5 seconds.

[0023] Furthermore, during the hot pressing process, the equipment is pressurized to 120 tons, and the hot pressing time is approximately 30-40 seconds.

[0024] Furthermore, the wall thickness of the sprayed starch solution is 0.2-1 mm.

[0025] Furthermore, the modified corn starch has a viscosity of 3000-3900 mPa·s, a whiteness of 70-83%, and a fineness of 75-85 μm.

[0026] The beneficial effects of this invention are:

[0027] 1. This invention completely solves the problem of PFAS in the anti-oil agent of traditional production process, and complies with the EU's requirement that tableware be fluoride-free.

[0028] 2: The fluorine-free oil-resistant agent of this invention is applied internally to the slurry, and its price is 110 million yuan / ton, and most of it is imported; the modified starch is inexpensive, only 7,000 yuan / ton, and it replaces waterproofing agents, oil-resistant agents and other chemicals to achieve the function of waterproofing and oil resistance. The application of modified starch greatly reduces production costs.

[0029] 3: The use of online hot-pressing spraying in this invention not only solves the problem of starch curing time, but also eliminates the need for subsequent hot-pressing curing, thus reducing energy consumption.

[0030] 4. The application of the modified starch spraying surface process of this invention greatly improves the stiffness of the product. Experiments show that the stiffness of a product with a wall thickness of 0.6mm after being sprayed with starch solution can be increased from a load of 7kg to 11kg, an increase of 57%.

[0031] 5. The application of the surface spraying process technology of this invention avoids the problems of water filtration and screen clogging and sticking caused by in-slurry sizing.

[0032] 6: The starch of this invention, after modification according to the following indicators: viscosity: ≤3300 mPa·s, whiteness: 83, fineness: ≥75, will no longer stick to the upper mold, and the hot pressing demolding speed is fast and efficient.

[0033] The surface starch solution spraying avoids the situation where vacuum adsorption draws the starch back into the slurry tank, thus improving the utilization rate of recycled slurry. Attached Figure Description

[0034] To more clearly illustrate the technical solutions in this invention or the prior art, the drawings used in the description of the embodiments or the prior art will be briefly introduced below. Obviously, the drawings described below are only for this invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0035] Figure 1 This is a schematic diagram of the process structure of an embodiment of the present invention. Detailed Implementation

[0036] To make the objectives, technical solutions, and advantages of this invention clearer, the invention will be further described in detail below with reference to specific embodiments.

[0037] Example 1

[0038] Raw material selection: Sugarcane is used as the main raw material for fiber pulp boards made from annual grass plants. The pulp is pulped for 2.5 minutes in a low-concentration hydraulic pulper to achieve a reasonable fiber dissociation degree before being transported to the mixing tank.

[0039] Mixing and preparation: In the mixing tank, the concentrated slurry is mixed and prepared in an appropriate ratio and stirred evenly to adjust the concentration of the slurry to 0.4%. During the pulping process, a fluorine-free anti-oil agent is applied to the slurry.

[0040] Slurry treatment: The prepared low-concentration slurry is pumped to the slurry supply tank and continuously and evenly stirred to prevent slurry fiber sedimentation.

[0041] Molding and Spraying: The prepared slurry is injected into the metal mesh of the molding mold via a slurry pump. A vacuum is applied for approximately 10 seconds to evenly distribute the plant fibers on the metal mesh, while simultaneously removing about 70% of the moisture. Excess moisture is returned to the water supply tank. Next, modified corn starch with a viscosity of 3000 mPa·s, whiteness of 70%, and fineness of 75 μm is added to the spraying tank and mixed with water at a ratio of 0.2%, with continuous stirring. Using a spraying machine, the spray nozzle is moved to evenly spray the mixed starch solution onto the wet blank in the hot press mold. The wall thickness of the sprayed starch solution is 0.3 mm, and the spraying time is approximately 5 seconds.

[0042] Hot pressing and subsequent processing: After spraying, the bottom hot pressing mold moves to the bottom of the upper hot pressing mold. The upper mold starts hot pressing for about 30 seconds, and the equipment pressurizes to 120 tons until the moisture content after hot pressing does not exceed 7%. When the upper mold returns to its original position, a robotic arm moves the hot-pressed tableware to the edge-cutting mold for die cutting, and the excess edge material is recycled. The cut products are then sorted, disinfected, packaged, and stored.

[0043] Example 2:

[0044] Raw material selection: Sugarcane is used as the main raw material for fiber pulp boards made from annual grass plants. The pulp is pulped for 2.5 minutes in a low-concentration hydraulic pulper to achieve a reasonable fiber dissociation degree before being transported to the mixing tank.

[0045] Mixing and preparation: In the mixing tank, the concentrated slurry is mixed and prepared in an appropriate ratio and stirred evenly to adjust the concentration of the slurry to 0.4%. During the pulping process, a fluorine-free anti-oil agent is applied to the slurry.

[0046] Slurry treatment: The prepared low-concentration slurry is pumped to the slurry supply tank and continuously and evenly stirred to prevent slurry fiber sedimentation.

[0047] Molding and Spraying: The prepared slurry is injected into the metal mesh of the molding mold via a slurry pump. A vacuum is applied for approximately 10 seconds to evenly distribute the plant fibers on the metal mesh, while simultaneously removing about 70% of the moisture. Excess moisture is returned to the water supply tank. Next, modified corn starch with a viscosity of 3300 mPa·s, whiteness of 83%, and fineness of 75 μm is added to the spraying tank and mixed with water at a ratio of 0.2%, with continuous stirring. Using a spraying machine, the spray nozzle is moved to evenly spray the mixed starch solution onto the wet blank in the hot press mold. The wall thickness of the sprayed starch solution is 0.3 mm, and the spraying time is approximately 5 seconds.

[0048] Hot pressing and subsequent processing: After spraying, the bottom hot pressing mold moves to the bottom of the upper hot pressing mold. The upper mold starts hot pressing for approximately 33 seconds, and the equipment pressurizes to 120 tons until the moisture content after hot pressing does not exceed 7%. When the upper mold returns to its original position, a robotic arm moves the hot-pressed tableware to the edge-cutting mold for die-cutting, and excess edge material is recycled. The trimmed products are then sorted, disinfected, packaged, and stored.

[0049] Example 3:

[0050] Raw material selection: Sugarcane is used as the main raw material for fiber pulp boards made from annual grass plants. The pulp is pulped for 2.5 minutes in a low-concentration hydraulic pulper to achieve a reasonable fiber dissociation degree before being transported to the mixing tank.

[0051] Mixing and preparation: In the mixing tank, the concentrated slurry is mixed and prepared in an appropriate ratio and stirred evenly to adjust the concentration of the slurry to 0.4%. During the pulping process, a fluorine-free anti-oil agent is applied to the slurry.

[0052] Slurry treatment: The prepared low-concentration slurry is pumped to the slurry supply tank and continuously and evenly stirred to prevent slurry fiber sedimentation.

[0053] Molding and Spraying: The prepared slurry is injected into the metal mesh of the molding mold via a slurry pump. A vacuum is applied for approximately 10 seconds to evenly distribute the plant fibers on the metal mesh, while simultaneously removing about 70% of the moisture. Excess moisture is returned to the water supply tank. Next, modified corn starch with a viscosity of 3500 mPa·s, whiteness of 75%, and fineness of 50 μm is added to the spraying tank and mixed with water at a ratio of 0.2%, with continuous stirring. Using a spraying machine, the spray nozzle is moved to evenly spray the mixed starch solution onto the wet blank in the hot press mold. The wall thickness of the sprayed starch solution is 0.3 mm, and the spraying time is approximately 5 seconds.

[0054] Hot pressing and subsequent processing: After spraying, the bottom hot pressing mold moves to the bottom of the upper hot pressing mold. The upper mold starts hot pressing for about 36 seconds, and the equipment pressurizes to 120 tons until the moisture content after hot pressing does not exceed 7%. When the upper mold returns to its original position, a robotic arm moves the hot-pressed tableware to the edge-cutting mold for die cutting, and the excess edge material is recycled. The cut products are then sorted, disinfected, packaged, and stored.

[0055] Example 4:

[0056] Raw material selection: Sugarcane is used as the main raw material for fiber pulp boards made from annual grass plants. The pulp is pulped for 2.5 minutes in a low-concentration hydraulic pulper to achieve a reasonable fiber dissociation degree before being transported to the mixing tank.

[0057] Mixing and preparation: In the mixing tank, the concentrated slurry is mixed and prepared in an appropriate ratio and stirred evenly to adjust the concentration of the slurry to 0.4%. During the pulping process, a fluorine-free anti-oil agent is applied to the slurry.

[0058] Slurry treatment: The prepared low-concentration slurry is pumped to the slurry supply tank and continuously and evenly stirred to prevent slurry fiber sedimentation.

[0059] Molding and Spraying: The prepared slurry is injected into the metal mesh of the molding mold via a slurry pump. A vacuum is applied for approximately 10 seconds to evenly distribute the plant fibers on the metal mesh, while simultaneously removing about 70% of the moisture. Excess moisture is returned to the water supply tank. Next, modified corn starch with a viscosity of 3600 mPa·s, whiteness of 80%, and fineness of 79 μm is added to the spraying tank and mixed with water at a ratio of 0.2%, with continuous stirring. Using a spraying machine, the spray nozzle is moved to evenly spray the mixed starch solution onto the wet blank in the hot press mold. The wall thickness of the sprayed starch solution is 0.3 mm, and the spraying time is approximately 5 seconds.

[0060] Hot pressing and subsequent processing: After spraying, the bottom hot pressing mold moves to the bottom of the upper hot pressing mold. The upper mold starts hot pressing for approximately 37 seconds, and the equipment pressurizes to 120 tons until the moisture content after hot pressing does not exceed 7%. When the upper mold returns to its original position, a robotic arm moves the hot-pressed tableware to the edge-cutting mold for die-cutting, and excess edge material is recycled. The trimmed products are then sorted, disinfected, packaged, and stored.

[0061] Example 5:

[0062] Raw material selection: Sugarcane is used as the main raw material for fiber pulp boards made from annual grass plants. The pulp is pulped for 2.5 minutes in a low-concentration hydraulic pulper to achieve a reasonable fiber dissociation degree before being transported to the mixing tank.

[0063] Mixing and preparation: In the mixing tank, the concentrated slurry is mixed and prepared in an appropriate ratio and stirred evenly to adjust the concentration of the slurry to 0.4%. During the pulping process, a fluorine-free anti-oil agent is applied to the slurry.

[0064] Slurry treatment: The prepared low-concentration slurry is pumped to the slurry supply tank and continuously and evenly stirred to prevent slurry fiber sedimentation.

[0065] Molding and Spraying: The prepared slurry is injected into the metal mesh of the molding mold via a slurry pump. A vacuum is applied for approximately 10 seconds to evenly distribute the plant fibers on the metal mesh, while simultaneously removing about 70% of the moisture. Excess moisture is returned to the water supply tank. Next, modified corn starch with a viscosity of 3900 mPa·s, whiteness of 82%, and fineness of 85 μm is added to the spraying tank and mixed with water at a ratio of 0.2%, with continuous stirring. Using a spraying machine, the spray nozzle is moved to evenly spray the mixed starch solution onto the wet blank in the hot press mold. The wall thickness of the sprayed starch solution is 0.3 mm, and the spraying time is approximately 5 seconds.

[0066] Hot pressing and subsequent processing: After spraying, the bottom hot pressing mold moves to the bottom of the upper hot pressing mold. The upper mold starts hot pressing for about 40 seconds, and the equipment pressurizes to 120 tons until the moisture content after hot pressing does not exceed 7%. When the upper mold returns to its original position, a robotic arm moves the hot-pressed tableware to the edge-cutting mold for die cutting, and the excess edge material is recycled. The cut products are then sorted, disinfected, packaged, and stored.

[0067] We will use Type C specimens from ISO 1924-2:2014 to test the flexural strength of five different embodiments. Test results will include load (kg), stiffness, and hot-press draft speed. The test results are as follows:

[0068]

[0069] Based on the above experimental results, the test data of the finished product in Example 2 is the best.

[0070] This invention is intended to cover all such substitutions, modifications, and variations that fall within the broad scope of the appended claims. Therefore, any omissions, modifications, substitutions, or improvements made within the spirit and principles of this invention should be included within the scope of protection of this invention.

Claims

1. A process for the production of molded plant fiber pulp and modified starch mixed dinnerware characterized in that, It comprises the following steps: Step 1: The annual herbaceous plant fiber pulp board is crushed for about 2.5 minutes by a low-concentration water hydraulic pulper to achieve a reasonable fiber beating degree, and then the pulp is transported to a pulp mixing tank; Step 2: In the pulp mixing tank, the thick pulp is mixed and configured according to a certain proportion, and uniform stirring is performed, so that the concentration of the pulp is adjusted to 0.4%, and a fluorine-free oil-proof agent is applied in the pulp during the crushing process; Step 3: The low-concentration pulp solution is pumped to a pulp supply tank by a pulp pump, and uniform stirring is continuously performed to prevent the pulp fibers from precipitating; Step 4: The prepared pulp solution is injected onto the metal mesh of the forming mold by the pulp pump, and the plant fibers are uniformly distributed on the metal mesh by the action of vacuum for about 10 seconds, and the moisture is sucked to about 70%, and the excess moisture is returned to the water supply tank; Step 5: The formed wet embryo is transferred to the hot-pressing setting movable mold by a mechanical arm; Step 6: Modified corn starch is added to the spraying tank, mixed with water at a proportion of 0.2%, and continuously stirred; Step 7: The mixed modified corn starch solution is uniformly sprayed on the wet embryo in the hot-pressing mold by using a spraying machine to move the spray head, and the spraying time is about 5 seconds, and the use of modified starch achieves the effect of waterproof and oil-proof; Step 8: After spraying, the hot-pressing bottom mold is operated to the lower side of the hot-pressing upper mold, the upper mold is started to perform hot-pressing for 30-40 seconds, and the equipment is pressurized to 120 tons until the moisture content after hot-pressing is not more than 7%; Step 9: When the upper mold returns, the hot-pressed tableware is moved to the edge cutting mold by a mechanical arm for cutting, and the excess edge material is recycled; Step 10: The cut edge product is selected, disinfected, packaged, and stored; The modified corn starch has a viscosity of 3000-3900 mPa·s, a whiteness of 70-83%, and a fineness of 75-85 μm.

2. A process for the production of molded plant fiber pulp and modified starch blended tableware according to claim 1, characterized in that, The raw material of the plant fiber pulp board includes any one of sugarcane, reed, bamboo, straw, and wheat annual herbaceous plants.

3. A process for the production of moulded plant fibre pulp and modified starch based tableware according to claim 2, characterized in that, The spraying wall thickness of the modified corn starch solution in step 7 is 0.2-1 mm.

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